(4 min read)
Wobbly knees on the stairs. A clunk in the pelvis when you roll over in bed. Hips that feel like they might give way. If any of that sounds familiar, there's a reason for it.
It's not in your head. It's not a sign that something is wrong. It's physiology. And it has a name.
It starts with a hormone called relaxin
During pregnancy, your body produces a hormone called relaxin. The name is actually a pretty good clue as to what it does. It relaxes connective tissue, specifically the ligaments, tendons, and fibrous tissue around your joints, making them more pliable and stretchy.
This is completely intentional. Your pelvis isn't one rigid structure. It's made up of several bones held together by ligaments, and those ligaments need some give in them for your baby to move through the birth canal. Relaxin is one of the hormones that makes that possible.
But here's what most women aren't told. Relaxin doesn't only act on your pelvis. It acts on connective tissue throughout your entire body. Every joint. Every ligament. Which is why pregnancy can cause that characteristic waddle, increased arch in the lower back, and discomfort or instability in joints that have nothing to do with your pelvis at all, including your hips, knees, wrists, and ankles.
Why it doesn't just disappear after birth
This is where so many women get let down by the information they're given.
If you're not breastfeeding, relaxin levels do drop relatively quickly in the weeks following birth as your hormones begin moving back toward their pre-pregnancy pattern. But if you are breastfeeding, relaxin can remain elevated for some time after birth, and its effects on connective tissue may continue for as long as you're lactating.
What this means in real life is that the joint laxity you experienced during pregnancy doesn't necessarily resolve at six weeks postpartum. For many breastfeeding women, it continues for months. It may take a further period after weaning for hormone levels and joint stability to fully settle.
The six-week postpartum clearance was designed around wound healing and bleeding. It was never designed around the hormonal timeline of joint stability. So a woman who's given birth and is breastfeeding may be operating with lax joints for many months, and then returning to exercise, heavy lifting, or high-impact activity with a body that doesn't yet have the structural stability it will eventually have.
This isn't a reason to avoid movement. Progressive loading and thoughtful exercise are genuinely important for helping connective tissue remodel and regain its integrity. But it is a reason to progress carefully, prioritise stability and control, and listen to your body when it tells you something isn't quite right.
If you've been told it should be gone by now
If you're still experiencing clicking, instability, or pelvic pain beyond six weeks, especially if you're still breastfeeding, and someone has told you it should have resolved by now, that advice probably wasn't based on the hormonal reality of your body.
Relaxin doesn't know it's been six weeks. It responds to pregnancy and lactation, not a calendar.
So many women internalise this as something being wrong with them, when what's actually happening is that their body is still in the middle of a complex, longer-arc process that nobody took the time to explain. That's not a personal failing. That's a gap in the information you were given.
What can help
A women's health physiotherapist is one of the most underutilised and undervalued resources in the postpartum period. If you're experiencing joint instability, pelvic girdle pain, or a general sense that your body doesn't feel structurally sound, a women's health physio can assess what's going on, give you targeted exercises to build stability back, and help you understand what loads are appropriate for where you are right now.
In the meantime, be gentle with yourself. Your body is holding you together through a hormonally complex season. The integrity will come back. It just takes longer than anyone tells you.
Disclaimer: The information presented by Fill Your Cup is not a substitute for independent professional advice. Nothing contained here is intended to be used as medical advice and it's not intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professional's advice.
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